This invention basically relates to a helmet and associated strap. Helmets are used for a wide variety of purposes. Special helmets are worn e.g. by construction workers, miners, firemen and rescue services as a protection against falling objects. Soldiers have always worn helmets in military exercises and battles. There are also many types of special helmets for sports use, e.g. for ice hockey players, for American Football players, for baseball players, for skiers, drivers of bobsleighs and sledges, cyclists and horse riders etc. etc.. The use of helmets by motorcyclists on public roads is also very common, and indeed required by law in many countries. This invention relates to helmets in general, for any helmet has to be secured when worn so that it will remain in place even if the wearer makes abrupt head movements, and so that it does actually fulfil its protective function in the event of any serious incident. As a general rule, the helmet is held in place by means of a two-part strap that is attached to the helmet, the length of which can be adjusted progressively or continuously, and which is joined together when worn e.g. by a hook or a snap-lock. Sometimes the end of a strap is passed through two eyelets on the opposite side of the helmet and then pulled back between these two eyelets so that the strap is secured by means of friction. Other straps are secured by Velcro fasteners or press-buttons.
In many cases, conventional straps are uncomfortable to use, or the length of the strap cannot be adjusted quickly and easily. The adjusting operation is impossible, or very difficult, to accomplish with one hand, even though this would be highly desirable, especially on helmets for cyclists, climbers, horse riders and similar. Very often, the length of the strap cannot be continuously adjusted.
On American Football helmets, for example, there are two straps on either side of the helmet which converge at an angle on a chin protection element forming a trough-shaped moulded piece which cups the chin, to which the four straps are attached. To put on a helmet of this type, the wearer has to adjust the length of all four straps, for which purpose buckles with press-button parts are provided. Once the wearer has adjusted the length of the four straps, someone else often has to help by pressing the buckles of the four straps onto the press-button parts on the helmet to produce the press-button connection. The straps are virtually impossible to adjust whilst the helmet is being worn, and certainly not by the wearer of the helmet himself.